1. Field of the Invention
The present invention relates to bow hunting and, more particularly, to a device for improving penetration of an arrow into a target and, most particularly, to a slide hammer impact enhancement system for an arrow used for bow hunting.
2. Background Information
A number of inventions concerned with impact enhancement devices for arrows have been granted patents. Taylor et al., in U.S. Pat. No. 4,489,949, describe an “improved” arrow construction which, by the partial or complete elimination of tail feathers as a means for stabilizing flight trajectory, improves both the speed and the accuracy of the arrow. A resilient stabilizing tail is substituted for tail feathers which substantially eliminates aerodynamic drag. In addition, the invention contemplates the use of a “shock piston” within the interior of the arrow shaft, which serves to increase arrow penetration in the target by striking the arrow head after the initial target impact. The enlarged head of the “shock piston” includes an elongated stabilizer that moves through a channel in the nock. The stabilizer is positioned within the arrow when launched, moves rearward out of the nock, then moves back inside the arrow when it hits the target.
In U.S. Pat. No. 4,900,038, Czetto et al. disclose an arrow projectile comprising an elongated, linearly configured body, having a hollow interior portion extending along the length thereof and preferably having a pointed, closed first end and an oppositely disposed second end which may have fletchings, as in typical arrow construction. Kinetic energy transferring members are captivated within the hollow interior portion of the body and movable between a first portion adjacent the rear end upon initial flight of projectile from a projecting device and transferable toward the leading end to a second position of impact so as to cause successive bursts or thrusts occurring as the energy transferring slide member impacts upon the leading end of the body and one another. The interior of the arrow shaft includes multiple sets of stationary magnets (36, 38; 44, 46; etc.) with a magnetically attracted weight (30, 32, 34) positioned between the magnet sets. The weights are complex in shape to minimize friction with the interior of the arrow shaft.
U.S. Pat. No. 6,375,586, by Cousins et al., discloses a device to increase an arrow's kinetic energy, and hence the force on target impact, without a substantial decrease in the velocity of the arrow as compared to the same arrow without such devices. The impact-enhancing devices are insertable into an arrow shaft and include an impact-enhancer weight (28) which is freely moveable within the arrow shaft, with the weight (28) sliding on a central guide shaft a (24). The impact-enhancer weight will thus be propelled in response to rapid deceleration of the arrow (i.e., caused by the arrow head striking a target area). The relatively high velocity movement of the impact-enhancer weight will create a secondary kinetic energy effect which drives the arrow head further into the target area. That is, the impact-enhancer weight will be propelled forward at a sufficiently high velocity and strike a rearward region adjacent the arrow head, thereby generating a secondary impact force (i.e., secondary to the initial target impact of the arrow itself) causing the arrow head to penetrate deeper into the target area. In such a manner, the effect of the arrow head is enhanced.
Kuhn, in U.S. Pat. No. 6,588,280, describes a cylindrical arrow ferrule device that is inserted between the arrowhead and the main shaft of an arrow or as an integral part of a hollow arrow shaft. A key feature of the invention is an internal actuator that slides down an inner chamber of the device. Prior to impact, the actuator is magnetically coupled to the aft wall of the chamber; but, upon impact, the resulting force releases the actuator that then slides forward to impact the forward wall of the chamber. This actuation provides the same inelastic collision associated with a dead-blow hammer, thereby driving the arrow into the target.
In U.S. Pat. No. 8,241,157, Russell et al. disclose a projectile system that includes a hollow portion with a weight that is movably secured within the hollow portion of the projectile insert system. Some embodiments include an attracting device, rigidly secured at a first end of the hollow portion, with the attracting device removably securing the weight, where the hollow portion provides a pathway for the weight to travel when a force is exerted on the projectile insert system that causes the weight to become unsecured from the attracting device. In all examples and drawings, the attaching device (106, 208 or 308), which is a magnet, is secured in a stationary position. Only the weight moves on impact, not the magnet.
Shao, in U.S. Patent No. 2006/0154756 describes a dart having a substantially hollow shaft and one or a plurality of removable weights to be placed in the lumen of the shaft so that the weight of the dart is adjustable. This results in a secondary momentum when the dart hits a dartboard. The weight can be magnetic or nonmagnetic.
Applicants have invented a slide hammer impact enhancement system for an arrow that is easily incorporated into commercially available arrows. The impact enhancement system of the present invention is inexpensive, reusable, and readily transferred between arrows should other portions of the arrow be damaged. The slide hammer impact enhancement system is a novel improvement over the existing technology in this field of art.